Solid-state imaging device capable of inhibiting peeling of fixed charge film, method of manufacturing the same, and electronic device

Abstract

The present technology relates to a solid-state imaging device capable of inhibiting peeling of a fixed charge film while inhibiting dark current, a method of manufacturing the same, and an electronic device. A solid-state imaging device provided with a semiconductor substrate in which a plurality of photodiodes is formed, a groove portion formed in a depth direction from a light incident side for forming an element separating unit between adjacent photoelectric conversion elements on the semiconductor substrate, a first fixed charge film formed so as to cover a surface of a planar portion on the light incident side of the semiconductor substrate, and a second fixed charge film formed so as to cover an inner wall surface of the groove portion formed on the semiconductor substrate is provided. The present technology is applicable to a backside illumination CMOS image sensor, for example.

The invention claimed is: 
     
       1. A light detecting device comprising:
 a first photoelectric conversion region and a second photoelectric conversion region disposed in a semiconductor substrate, wherein the first photoelectric conversion region is adjacent to the second photoelectric conversion region; 
 a groove portion disposed in the semiconductor substrate below a light receiving plane of the semiconductor substrate in a cross-sectional view, wherein the groove portion is disposed between the first photoelectric conversion region and the second photoelectric conversion region; 
 a first film disposed above the light receiving plane, wherein the first film includes a hafnium oxide, and wherein an opening of the groove portion is blocked by the first film in the cross-sectional view; and 
 a second film covering an inner wall surface of the groove portion, wherein the second film includes one of an aluminum oxide, zirconium oxide, tantalum oxide, or titanium oxide. 
 
     
     
       2. The light detecting device of  claim 1 , wherein the opening of the groove portion is disposed below the light receiving plane. 
     
     
       3. The light detecting device of  claim 1 , wherein the opening of the groove portion is higher than the first photoelectric conversion region and the second photoelectric conversion region in the cross-sectional view. 
     
     
       4. The light detecting device of  claim 1 , wherein the first film is a first fixed charge film. 
     
     
       5. The light detecting device of  claim 4 , wherein a large portion of the light receiving plane is covered by the first fixed charge film. 
     
     
       6. The light detecting device of  claim 1 , wherein the second film is a second fixed charge film. 
     
     
       7. The light detecting device of  claim 6 , wherein a large portion of the inner wall surface is covered by the second fixed charge film. 
     
     
       8. The light detecting device of  claim 1 , wherein a light shielding portion is disposed above the groove portion. 
     
     
       9. The light detecting device of  claim 8 , wherein the light shielding portion includes one of W or Al. 
     
     
       10. The light detecting device of  claim 1 , wherein the light receiving plane is opposite to a side of a wiring layer. 
     
     
       11. The light detecting device of  claim 1 , wherein the light detecting device comprises a backside illumination Complementary Metal Oxide Semiconductor (CMOS) image sensor. 
     
     
       12. A light detecting device comprising:
 a first photoelectric conversion region and a second photoelectric conversion region disposed in a semiconductor substrate, wherein the first photoelectric conversion region is adjacent to the second photoelectric conversion region; 
 a groove portion disposed in the semiconductor substrate below a light receiving plane of the semiconductor substrate in a cross-sectional view, and wherein the groove portion is disposed between the first photoelectric conversion region and the second photoelectric conversion region in the cross-sectional view; 
 a first film disposed above the light receiving plane, wherein the first film includes a hafnium oxide, wherein an opening of the groove portion is blocked by the first film in the cross-sectional view, and wherein the first film comprises a first portion, a second portion, and a third portion, and wherein the second portion is disposed between the first portion and the third portion; and 
 a second film covering an inner wall surface of the groove portion, wherein the second film includes one of an aluminum oxide, zirconium oxide, tantalum oxide, or titanium oxide. 
 
     
     
       13. The light detecting device of  claim 12 , wherein the first portion and the third portion of the first film are disposed above the first photoelectric conversion region and the second photoelectric conversion region, respectively, in the cross-sectional view. 
     
     
       14. The light detecting device of  claim 12 , wherein the second portion of the first film is disposed above the groove portion in the cross-sectional view. 
     
     
       15. The light detecting device of  claim 12 , wherein the second portion of the first film is in direct contact with the second film. 
     
     
       16. The light detecting device of  claim 12 , wherein the first portion, the second portion, and the third portion of the first film are linked together. 
     
     
       17. An electronic device comprising:
 a light detecting device including:
 a semiconductor substrate; 
 a first photoelectric conversion region and a second photoelectric conversion region disposed in the semiconductor substrate, wherein the first photoelectric conversion region is adjacent to the second photoelectric conversion region; 
 a groove portion disposed in the semiconductor substrate below a light receiving plane of the semiconductor substrate in a cross-sectional view, and disposed between the first photoelectric conversion region and the second photoelectric conversion region in the cross-sectional view; 
 a first film disposed above the light receiving plane, wherein the first film includes a hafnium oxide, and wherein an opening of the groove portion is blocked by the first film in the cross-sectional view; and 
 a second film covering an inner wall surface of the groove portion, wherein the second film includes one of an aluminum oxide, zirconium oxide, tantalum oxide, or titanium oxide.